In a conventional development device, a surface of a photosensitive drum evenly charged by a charge device is exposed by an exposure device to form an electrostatic latent image. And then, the electrostatic latent image is developed by the development device to form a toner image as a developer image on the photosensitive drum. After that, the toner image is transferred to a sheet, and is fixed on the sheet. Thereby, an image is formed on the sheet. At this time, in the development device, toner supplied by a toner cartridge is supplied by a supply roller to a development roller. An even toner layer is formed on the development roller with a restriction blade to develop the toner image on the photosensitive drum. During the development, the toner that remains on the development roller is collected with a toner collection roller, and is scraped off the toner collection roller with a toner collection blade (see JP Laid-Open Patent Application No. 2011-197219, columns 0014-0018, FIG. 2, for example).
However, in the conventional art, while the collection toner scraped off the toner collection roller is mixed with new toner supplied from the toner cartridge by an agitation member of the development device, toner that accumulates in the vicinity of the development roller exists. The collection toner is unnecessarily damaged, and a charging characteristic thereof deteriorates in comparison with the new toner. When the collection toner is insufficiently mixed with the new toner, portion having a high proportion of the collection toner occurs. Therefore, there is a problem that detects of the developer image such as fog and blur occur.
An objection of the present invention is to improve image quality of the developer image to solve such a problem.